You can grab the package source and compile it on your machine. Download the source from the Ubuntu 11.10 package page (you need all three files: .dsc, .orig.tar.gz and .debian.tar.gz). Install development tools and build dependencies, compile the package, install run-time dependencies and install the package.

A simple way to install RVM is to follow the instructions at the developer's site (in fact, the site says "Please use the install process(es) from this site only, as this is the only supported installation types and methods."):

curl -L get.rvm.io | bash -s stable

Load RVM:

source ~/.rvm/scripts/rvm

Find the requirements (follow the instructions):

rvm requirements

Install ruby:

rvm install 1.9.3

On my system (12.04), this all went without a hitch; requirements listed were easy to find and install using apt-get.

4. Install a ruby

Errors on your instructions when i hit "install rvm". See here: prntscr.com/5oykdf -- unmet dependencies, but shouldn't it just download it by itself? this is why i find installing stuff in linux soooo frustrating. Everyone's setup is different. Why can't it just install the dependencies too?
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duckxJan 5 at 22:35

Yes, it should download all dependencies itself. Really weird the messages in your screenshot. As you can see here, by example, gawk is available on Precise. Appears you don't have any sources in your /etc/apt/sources.list file.
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Rael Gugelmin CunhaJan 6 at 0:27